1. Field of the Invention
The present invention relates to a technique of performing sign language by a robot, and more specifically, to a sign language action generating device which generates a sign language action generated by connecting each sign language action corresponding to a word used in a sign language by a robot, and a communication robot equipped with the sign language action generating device.
2. Description of the Related Art
Japan Patent Publication No. 3235622 discloses a technique of performing sign language by a communication robot with an intention to have communication with a human. However, the communication robot described in Japan Patent Publication No. 3235622 is not a real robot but an animated robot displayed on a screen. Thus, Japan Patent Publication No. 3235622 does not disclose generation of an arm trace produced by both arms of a robot or generation of an action such as, for example, a rotation of an arm thereof about an axis, which are necessary for a rotation of a real arm to perform sign language. If an arm of a real robot bumps against other member or the like, some parts of the robot may get deteriorated or break down. Hereinafter, an undesirable state of an arm in which the arm comes in contact with or collides against other member, or becomes an obstacle of other member even without any contact therewith is collectively referred to as an interference.
Various techniques for avoiding interference of an arm of a robot have been known in a field of industrial robots. A number of techniques for generating a trace of an arm of various robots operated in a workplace such as a factory have been disclosed (see, for example, Japanese Laid-Open Patent Application, Publication No. 2011-115877. The technique for generating a trace of an arm of such a robot assumes, however, that the robot is operated based on a positional relationship between a work and a holding part (a hand) at an end of the arm.